Oat Response to Oat Response to Imazapic ResiduesImazapic Residues

E. P. Prostko, T.L. Grey, and R. N. Morgan

Department of Crop & Soil Sciences

University of Georgia

TiftonWSSA - 2005

Imazapic Imazapic trade named - CADRE BASF product labeled for peanut in 1996 postemergence

– nutsedges– broadleaf– small grasses

very popular– 64% in GA

$15-16/A rotation restrictions

Cadre Rotational RestrictionsCadre Rotational Restrictions

Small Grains in GeorgiaSmall Grains in GeorgiaPlanted AcresPlanted Acres

100

270

380

80

230

330

0

75

150

225

300

375

450

Oats Rye Wheat

Crop

Acr

es

(X 1

000)

2002-2003

2003-2004

Source: GASS

Materials and Methods - IMaterials and Methods - I

small plot techniques 4 replications imazapic @ 1.44 ozs/A

applied to bare ground first week of May, June,

July , August, September ‘Coker 227’ oats planted

first week of October 3 locations no tillage after initial bed

formation

Materials and Methods - IIMaterials and Methods - IIData CollectedData Collected

stand counts– 1-2 WAP

forage yields– machine harvested

in December and January

grain yields– machine harvested

in May

Soil TypesSoil Types

Tifton Plains

pH 6.0 6.01

OM (%) 1.24 <1.0

Sand (%) 96 71

Silt (%) 2 13

Clay (%) 2 16

ResultsResults

The influence of imazapic on oat standThe influence of imazapic on oat stand

8593 92

8795 92

0

20

40

60

80

100

Untre

ated M

ayJu

ne July

AugSep

t

Timing

plan

ts/m

eter

Averaged over 3 tests P = 0.60

The influence of imazapic on forage yieldThe influence of imazapic on forage yield

25462745

25442269

1977

975

0

500

1000

1500

2000

2500

3000

Untre

ated M

ayJu

ne July

AugSep

t

Timing

Dry

wei

ght

(kg/

ha)

Averaged over 3 tests

aa

aab

b

c

LSD

The influence of imazapic on grain yieldThe influence of imazapic on grain yield

32603029 2936

3135 3186 3257

0

700

1400

2100

2800

3500

Untre

ated M

ayJu

ne July

AugSep

t

Timing

kg/h

a

Averaged over 3 tests P = 0.1476

Cadre Injury SymptomsCadre Injury Symptoms

Untreated

Sept 3

June 4

May 1

Aug 5

July 1

CADRE/OATS TESTDecember 3, 2002

Oats planted October 2, 2002

CADRE/OATS TESTJanuary 21, 2003

Untreated

Sept 3

June 4

May 1

Aug 5

July 1

Oats planted October 2, 2002

Untreated Cadre 1 Month Before Planting

Photo 21 DAP, Tifton 2003

SummarySummary

oat stand was not reduced by any timing of imazapic

oat forage yield reduced when imazapic was applied in August and September (1-2 months before planting)

oat grain yield was not reduced by any timing of imazapic

ConclusionsConclusions

the oat rotation restriction does not need to be 18 months

should be equivalent to other small grains (4 months)